massive pro-democracy demonstrations in Hong Kong, organizers say at least 1.7 million people came out in force on Sunday as tensions there rise with China. Ian Pannell is on the ground there in Hong Kong with the very latest. Good morning, Ian. Reporter: Yeah. Good morning, Cecilia. Extraordinary scenes here as hundreds of thousands defied the torrential rains, threats from China, and police marching on the streets. We saw young and old, rich and poor, umbrellas that have long been a symbol of protests here, held high. There were over 1.5 million on the streets and if that's true, that's a quarter of the city's entire population. Even more remarkable, it was entirely peaceful. No repeats of the violence we have seen. Also the Chinese who released this ominous video over the weekend, never left their positions despite threats from beijing. Ian, you have been on the ground there all weekend right in the middle of it. What are these protesters telling you about how long they plan to keep going? Reporter: Cecilia, they're saying it's now or never, and that's because they have been here before, and it didn't work. What I'm hearing repeatedly is they won't stop until they demand justice and democracy. If it backs down, it sets a dangerous precedent, and president trump is now saying, it would be hard to do a trade deal. Look at the skyline behind me. You have got bank of America right there, and the Chinese people's liberation army almost next door. It's one of the world's leading financial centers and it would be hard to continue business as usual for America, China, or indeed the global economy. A lot on the line. Thank you. We turn to new questions

This transcript has been automatically generated and may not be 100% accurate.

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